the full version and the trial are identical, the trial only checks at startup if you are in the trial period. So I heavily doubt that your problems would be fixed with the full version.
It sounds like you have a hardware problem somewhere in the system. Clips turning pink is usually a sign of a corrupted media file.

Try running the disk check of DiskUtility onto your media drives. Do they show up as okay?
What codec and format are you acquiring to your media drives? A single SATA drive is fast enough for SD or maybe compressed HD, but if you try to acquire uncompressed HD you could run into drive performance issues.
Where is your Blackmagic board located within your system? I am not sure where it should be, bt maybe Wick knows that.
Do you have anything else within the system (PCI-cards or unusual USB or FireWire devices)?